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2021 Vol.31, Issue 6 Preview Page

Original Article

A Fundamental Study on Shearing/Bonding Characteristics of Interface Between Rock Mass and Backfills in Mine Openings

폐광산 채움재와 암반 경계부의 전단 및 접합특성에 관한 기초 연구

Byung-Ryeol Kim1
,
Hyeon-woo Lee2
,
Young-Jin Kim1
,
Kye-Hong Cho3
,
Sung-Oong Choi4*
김 병렬1
,
이 현우2
,
김 영진1
,
조 계홍3
,
최 성웅4*
1Researcher, Korea Institute of Limestone & Advanced Materials
2Master’s course student, Dept. of Integrated Energy and Infra system, Kangwon National University
3Director, Korea Institute of Limestone & Advanced Materials
4Professor, Dept. of Energy and Resources Engineering/Integrated Energy and Infra system, Kangwon National University
1한국석회석신소재연구소 연구원
2강원대학교 신산업개발T-EMS융합전공 석사과정
3한국석회석신소재연구소 연구소장
4강원대학교 에너지･자원공학전공 및 신산업개발T-EMS융합전공 교수
*Corresponding Author
31 December 2021. pp. 623-646
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Abstract

As the demand for electric power increases with acceleration of electrification at home and abroad, the needs for coal-fired electrical power plant are accordingly increased. However, these coal-fired electrical power plants induce also many environmental problems such as increase of air pollutants, increase of possibility of land contamination by reclamation of coal ash, even though these power plants have a good economical efficiency. In case of a by-product of coal-fired electrical power plants, only 70% of them are recycled and the remaining 30% of by-product are fully buried in surrounding ground. Consequently, this study deals with coal ash backfilling mechanism in abandoned mine openings for the purposes of increasing the coal ash recycling rate as well as securing the mine area stability. In order to analyze the backfill and ground reinforcement by interaction between rock mass and backfills, the copying samples of discontinuous surface with different roughnesses were produced for bond strength tests and direct shear tests. And statistical analysis was also conducted to decide the characteristics of bond and shear behavior with joint roughness and their curing day. Numerical simulations were also analyzed for examining the effect of interface behavior on ground stability.

Keywords
Coal-ash
Backfilling in abandoned mine
Interface between rock mass and backfills
Bond strength
Shear behavior

국내외적으로 전기화의 가속으로 인해 전력수요가 급증됨에 따라, 석탄화력발전소의 수요가 늘어나고 있다. 석탄화력발전소는 경제적으로 많은 이점이 있지만, 대기오염물질 증가, 발전회의 매립 처분에 의한 오염 유발 가능성 등의 환경적인 문제를 수반하고 있다. 특히, 발전부산물인 발전회의 경우에는 재활용률이 70%에 그치고 있으며, 나머지는 전량 매립되고 있다. 본 연구에서는 발전회의 재활용률을 증대시키고 지하에 위치하는 폐광산의 지반 안정성을 확보하기 위하여, 발전회를 폐광산 채움재로 이용하여 지하 폐광산의 채굴 공동을 충전하는 방안에 대한 기초연구를 수행하였다. 암반과 폐광산 채움재의 접합부에서 상호작용에 의한 충전 및 지반보강 효과를 분석하기 위하여, 다양한 거칠기를 갖는 절리면 모사 시료를 제작하여 접합강도 시험과 직접 전단시험을 수행하고 이에 대한 통계분석을 수행하여 절리면의 거칠기와 재령일에 따른 접합 및 전단거동 특성을 규명하였다. 또한 접합부 거동특성이 전산해석 기법을 이용한 지반안정성 분석에 미치는 영향을 검토하기 위하여 지하광산을 모델링하고 접합부 유무에 따른 거동특성을 비교하였다.

키워드
발전회
폐광산 채움재
암반-채움재 접합부
접합강도
전단 거동
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Information
  • Publisher :Korean Society for Rock Mechanics and Rock Engineering
  • Publisher(Ko) :한국암반공학회
  • Journal Title :Tunnel and Underground Space
  • Journal Title(Ko) :터널과 지하공간
  • Volume : 31
  • No :6
  • Pages :623-646
  • Received Date : 2021-12-13
  • Revised Date : 2021-12-17
  • Accepted Date : 2021-12-20
  • DOI :https://doi.org/10.7474/TUS.2021.31.6.623
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